Field of the Invention
The present invention relates to electrical filters, and, more specifically but not exclusively, to high-power, high-quality-factor, tunable-bandwidth bandpass filters suitable for use, e.g., in combining contiguous, duplexed signals in WiMAX and LTE systems.
Description of the Related Art
Certain advanced mobile wireless standards, including the Worldwide Interoperability for Microwave Access (WiMAX) standard (IEEE 802.16) and the 3rd Generation Partnership Project (3GPP®) Long Term Evolution (LTE®) standard, require transmission channels to have a bandwidth that can vary, e.g., from a few megahertz to more than 10 MHz. As more and more consumers use WiMAX and LTE devices, the width of the frequency band allocated for such devices at a base station may be increased to provide an increased data transmission capacity, while the width of the frequency bands allocated for second-generation (2G) wireless devices at the base station may be decreased. As such, it would be desirable to have a bandwidth-tunable, low-insertion-loss, bandpass filter for use in advanced wireless base stations.